The present invention relates to fluid couplings, and more particularly to those having a fluid channel which is inclined with respect to a direction orthogonal to the opposed end faces of the component coupling members of the coupling.
Fluid couplings are already known which comprise first and second coupling members each having a gasket holding annular ridge on a butting end face thereof, and an annular gasket interposed between the two coupling members. The conventional fluid couplings are generally so constructed that the flow channel of each coupling member is orthogonal to the butting end face.
For use in semiconductor manufacturing equipment or the like, we have proposed a fluid control apparatus 4 which comprises a massflow controller 3 and shutoff-opening devices 1, 2 provided respectively at the left side and right side of the massflow controller 3 as shown in FIG. 7. Each of the shutoff-opening devices 1, 2 comprises a plurality of valves 6, 7 (8, 9, 10) each having an inlet and an outlet in a lower surface thereof, and a valve mount 28 (29) having the valves 6, 7 (8, 9, 10) removably installed thereon from above as arranged in a direction. The valve mount 28 (29) comprises an inflow channel forming member 30 (34) having a channel in communication with the inlet of the valve 6 (8) disposed at one end thereof, one or a plurality of communication channel forming members 31 (36, 38) having a channel for causing the outlet of one of the valves 6 (8, 9) to communicate with the inlet of the valve 7 (9, 10) adjacent thereto, and an outflow channel forming member 33 (39) having a channel in communication with the outlet of the valve 7 (10) disposed at the other end of the mount (see Japanese Patent Application No. 278473/1997).
Indicated at 5 (11) in the drawing is a check valve comprising a left valve body 22 (25) having coupling portions 40, 41 (60, 61), a central valve body 23 (26), and a right valve body 24 (27). Indicated at 32 (35, 37) is a subchannel forming member comprising a coupling holding member 47 (51, 53) and a coupling portion 48 (52, 54). The massflow controller 3 has rectangular parallelepipedal extensions 49, 50 provided at the lower end thereof and each formed with a channel having a downward opening. Each on-off valves 6 (7, 8, 9, 10) comprises a valve body 12 (14, 16, 18, 20), and an actuator 13 (15, 17, 19, 21) mounted on the valve body from above for suitably shutting off or opening a channel through the valve body 12 (14, 16, 18, 20). Flanges 12a, 14a, 16a, 18a, 20a provided at the lower ends of the respective valve bodies 12, 14, 16, 18, 20 and rectangular when seen from above are connected to the valve mount 28 or 29 with screws (not shown) driven in from above.
In each shutoff-opening device 1 (2), the channel forming member 30 (38) may comprise a plurality of members 42, 43, 44, 45, 46 (55, 56, 57, 58, 59) in combination so as to have a U-shaped channel. Further the channel forming member 31 (33, 34, 36, 39) may consist only of a blocklike coupling member having a V-shaped channel 31a, (33a, 34a, 36a, 39a). The blocklike coupling members 31, 33, 34, 36, 39 then have the advantage of being reduced in the number of components and easy to heat by a heater.
Fluid control apparatus of the type described are generally used in systems of low pressure difference or systems of great flow rate, and it is desired that the apparatus be reduced in pressure losses to ensure an increased flow rate.
However, as compared with channel forming members having a U-shaped channel, the blocklike coupling members 31, 33, 34, 36, 39 formed with a V-shaped channel 31a, (33a, 34a, 36a, 39a) have a disadvantage from the viewpoint of increasing the flow rate since the diameter of the channel is smaller even if the opening of the channel has the same diameter as that of the U-shaped channel.